1. Field of the Invention
The present invention relates to an image formation device, an image formation method, a program, and an image forming product for forming an image formed of dots in which multiple dot sizes are mixed.
2. Description of the Related Art
In recent years, with the rapid progress of an ink jet technique, color and large size printing, in which high speed and high image quality are compatible, has been realized by ink-jet-type image formation devices. This kind of device is used in, particularly, a wide field in application to signs and display, and is also applicable to printing of, for example, a storefront point of purchase (POP), wall poster, outdoor advertising, a signboard, and the like.
In this ink jet type, liquid droplets of a plurality of types of ink (for example, CMYK inks) are ejected onto a recording medium so as to form a plurality of dots, thereby obtaining printed matter. For example, when an image is formed using dots with different sizes, there have been proposed various halftoning techniques in which an increase in image quality and reduction in calculation processing amount are compatible.
JP4375050B (claim 1, [0152] to [0155], FIG. 26, etc.) has proposed a method of determining dot sizes for pixels turned on in accordance with sizes of threshold values at positions corresponding to the pixels from the results of binarization processing using threshold matrices. More specifically, there has been proposed a method of sequentially allocating increasing dot sizes in an ascending order of threshold values (order values) when the number of large-size dots, the number of middle-size dots, and the number of small-size dots are specified.